Abstract
In order to study the role of tissue lipids in cellular reaction to injury in cerebral tissue, we produced cerebral infarct in rats by way of embolization of homologous blood, and we chemically, chronologically measured tissue lipids in the infarcts. The corresponding tissue changes were histologically studied as well.
Tissue phospholipids, essential components of membranes of cells and organellae, rapidly decreased to 79.8% of the controls in a day or two after injury. Histological changes at this time corresponded to tissue edema. On 3rd to 5th day when tissue damage was most advanced with many foamy macrophages in the center of infarcts, phospholipids still remained significantly low associated with a slight increase of triglycerides in the infarcted areas. The foamy macrophages were full of sudanophilic and osmiophilic granules. Later on, along with healing process, phospholipids gradually recovered to the same level as the controls by the 14th day. The infarcted areas at this point showed prominent proliferation of astroglia with still remaining foamy macrophages.
We presume that catabolized tissue phospholipids by released enzymes in the infarcted areas will return into blood circulation, and that uncatabolized phospholipids as well as certain other lipids will be phagocytized by macrophages. It is suggested that sudanophilic and osmiophilic granules in the foamy macrophages must be made up of not only triglycerides but also free fatty acids and cholesterol ester.
